Adhension Of Streptococcus Mutans To The Surface Of Different Alloy Meterials In Vitro

Various causes lead to tooth defects,edentulous, affect the face esthetics,pronunciation and chewing.Prosthesis is a reliable and effective method to slove theseproblems, alloys are indispensable materials.However,oral original environmentchanges when the prosthesis put into the mouth, resulting in the original flora, varioustypes of bacterial adhesion to the surface of the prosthesis and cause a series of oraldisease, in which Streptococcus mutans has the highest detection rate. Weresearch the relationship between alloy materials with Streptococcus mutans adhesionin this experiment.Objective:To compare the Streptococcus mutans adhesion in different alloy material(Ni-Cralloy, Co-Cr alloy, Au-Pd alloy, Au alloy of74%,86%Au alloy)surfaces whichculture in the same condition. By comparing and analyzing the amount ofStreptococcus mutans adhesion on different alloy surfaces and the influencing factorsto guide our clinical practice better.Materials and Methods:Materials:5groups of alloy materials: Ni-Cr alloy, Co-Cr alloy, Au-Pd alloy,Au alloy of74%,86%Au alloy, n=5; Streptococcus mutans (Ua159). Methods:Grind and polished the specimens step by step, detected the surface roughness toensure the surface roughness (Ra)value had no significant differences.Aftersterilizated the specimens,put them into the MRS liquid medium which containStreptococcus mutans (UA159) and cultured anaerobic for48hours.Then diluted tothousandfold, cultured anaerobic in the MRS solid medium for48hours,count thenumber of colonies and accorded the dilution factor calculate the colony formingunits (CFU/ml)of the original broth further. Used SPSS16.0statistical softwarestatistical analysis the data. Results:1.Used the one-way ANOVA to analysis the different alloy meterias`surfaceroughness values after grinding and polishing, the results show that: different alloymaterial surface roughness have no significant differences (P>0.05).2.In the same culture condition,the amounts of alloy surface adhesion ofStreptococcus mutans: Ni-Cr alloy> Co-Cr alloy> Au-Pd alloy>74%Au alloy>86%Au alloy.3.Used the one-way ANOVA analysis the amount of Streptococcus mutansadhesion in diffetent groups under the same culture condition,the results show that:there were significant differences (P<0.05)between different alloy meterials.4.Used the LSD (least significant Difference least significant difference)analysisthe adhesion amounts of Streptococcus mutans between groups under the sameculture condition, the results show: the adhesion amount of Streptococcus mutans:(1)There were significant differences (P<0.05)between nickel chromium alloy group andCo-Cr alloy group,Au-Pd alloy group,74%Au alloy group,86%Au alloy group;(2)There were significant differences (P<0.05)between Co-Cr alloy group and Ni-Cralloy, Au-Pd alloy group,,74%Au alloy group,86%Au alloy group;(3)There weresignificant differences (P<0.05)betweenAu-Pd alloy group and Co-Cr alloy, Ni-Cralloy group,74%Au alloy group,86%Au alloy group;(4) There were significantdifferences (P<0.05)between74%Au alloy group and the Ni-Cr alloy group,Co-Cralloy group, Au-Pd alloy group,but between86%Au alloy group has no significantdifferences (P>0.05);(5) There were significant differences (P<0.05)between86%Aualloy group and Ni-Cr alloy group,Co-Cr alloy group,Au-Pd alloy group,butbetween74%Au alloy group has no significant differences (P>0.05).Conclusion:1.The amount of Streptococcus mutans in Ni-Cr alloy and Co-Cr alloy surfacewere the most,74%and86%Au alloy surface were the least,semi-precious metalAu-Pd alloy between them.2.The higher of the precious metal containing,the less of the Streptococcusadhesion amount;the adhesion amount of Streptococcus mutans reduce with the precious metal containing, precious metal prosthesis control the adhesion ofStreptococcus mutans was better than the non-noble metal alloy prosthesis,we shouldtry to use the precious metal materials in clinica.3.Use conventional way to grind and polish different alloy meterials can reachthe clinical surface roughness requirements,and have no significant differencesbetween them.